From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1B03BC46475 for ; Thu, 25 Oct 2018 23:16:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B4AE32084A for ; Thu, 25 Oct 2018 23:16:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="PN7kCuTr" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B4AE32084A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727637AbeJZHvP (ORCPT ); Fri, 26 Oct 2018 03:51:15 -0400 Received: from mail.kernel.org ([198.145.29.99]:53488 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726796AbeJZHvP (ORCPT ); Fri, 26 Oct 2018 03:51:15 -0400 Received: from mail-wm1-f53.google.com (mail-wm1-f53.google.com [209.85.128.53]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E8DF220854 for ; Thu, 25 Oct 2018 23:16:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1540509399; bh=TVueKtyC7ZN2RBF4zdo1HxxlnmdPaZJQlS7zfNc5sYU=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=PN7kCuTrhXQIi8rkFF9uK0dW8JSw2pQkRKAkL5EArUjDdMLWPXx06Xw7GGdpFlxGH ggtCpYrMFF/VLrburM31uHcb4hnvmsaQBQJAsCeIE0tX22lm41AFVww7O61dA1EEcF If6IEyfDWg9Wr8NETZ263utycVEOFP5vhb3hF/T0= Received: by mail-wm1-f53.google.com with SMTP id w186-v6so3051591wmf.0 for ; Thu, 25 Oct 2018 16:16:38 -0700 (PDT) X-Gm-Message-State: AGRZ1gJPZQE7spWDN2mGq008km2relKbODKyzxz9VsTtqJgVyTRDT/qm GYfQXBR/UTSyO1aF5lnmZF8v0bHecVYCTVzHSiDK7w== X-Google-Smtp-Source: AJdET5dyTmjDKJAHtT7tqAR3N7o01nvQ0cKPwQRiCS6rMb5uiFpraU+Dz6kCW7IjNf+hh4/PtKBR+CtYzbYJsDLeLIs= X-Received: by 2002:a1c:1fcd:: with SMTP id f196-v6mr3548725wmf.19.1540509397463; Thu, 25 Oct 2018 16:16:37 -0700 (PDT) MIME-Version: 1.0 References: <20181023184234.14025-1-chang.seok.bae@intel.com> <20181023184234.14025-5-chang.seok.bae@intel.com> In-Reply-To: From: Andy Lutomirski Date: Thu, 25 Oct 2018 16:16:26 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [v3 04/12] x86/fsgsbase/64: Enable FSGSBASE instructions in the helper functions To: Andrew Lutomirski Cc: "Bae, Chang Seok" , Boris Ostrovsky , Juergen Gross , xen-devel , Ingo Molnar , Thomas Gleixner , "H. Peter Anvin" , Andi Kleen , Dave Hansen , "Metzger, Markus T" , "Ravi V. Shankar" , LKML Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Oct 24, 2018 at 12:16 PM Andy Lutomirski wrote: > > On Tue, Oct 23, 2018 at 11:43 AM Chang S. Bae wrote: > > +/* > > + * Interrupts are disabled here. Out of line to be protected from kprobes. > > + */ > > +static noinline __kprobes unsigned long rd_inactive_gsbase(void) > > +{ > > + unsigned long gsbase, flags; > > + > > + local_irq_save(flags); > > + native_swapgs(); > > + gsbase = rdgsbase(); > > + native_swapgs(); > > + local_irq_restore(flags); > > + > > + return gsbase; > > +} > > Please fold this into its only caller and make *that* noinline. > On further reading of the whole series, I retract this particular comment. But I do think that __rdgsbase_inactive() would be a better name.